1. Field of the Invention
The present invention is directed to recognition of recordings from their content, and, more particularly to combining fingerprint recognition with other information about a recording to increase reliability of recognition and to accomplish reliable recognition efficiently by using the least expensive forms of recognition first and layering on more complex forms as needed.
2. Description of the Related Art
There are many uses for recognition of audio (and video) recordings. Many of the uses relate to compensation or control by the rights holders for reproduction and performance of the works recorded. This use of such systems has increased in importance since the development of file sharing software, such as Napster, and the many other similar services available at the end of the twentieth century and the beginning of the twenty first century. Although the need for accurate recognition has been significant for several years, no system has been successful in meeting this need.
Another use of recording recognition is to provide added value to users when listening (or watching) recordings. One example is the CDDB Music Recognition Service from Gracenote, Inc. of Berkeley, Calif. which recognizes compact discs (CDs) and supplies information regarding a recognized CD, such as album name, artist, track names and access to related content on the Internet, including album covers, artist and fan websites, etc. While the CDDB service is effective for recognizing compact discs, there are several draw backs in using it to recognize files that are not stored on a removable disc, such as CD or DVD.
All audio fingerprinting techniques have “blind spots”, places where a system using that technique sees similarities and differences in audio where it shouldn't. By relying on just one fingerprinting technique, single source solutions are less accurate when encountering a ‘blind spot’.
One of the more popular uses for the Gracenote CDDB system is in applications that digitally encode audio files into MP3 and other formats. These encoding applications utilize Gracenote's CDDB service to recognize the compact disc being encoded and to write the correct metadata into the title and ID tags. Gracenote's CDDB service returns a unique ID (TUID) for each track and supports the insertion of such IDs in the ID3V2 tags for MP3 files. The TUID is both hashed and proprietary, and can only be read by the Gracenote system. However, the ID3V2 tags can easily be manipulated to store a TUID for one file in the ID3V2 tag for another file and therefore, the TUID alone is not a reliable identifier of the audio content in a file.
Gracenote's CDDB service also provides text matching capability that can be utilized to identify digital audio files from their file names, file paths, ID tags (titles), etc. by matching the text extracted by a client device to a metadata database of track, artist, and album names. Although this text matching utilizes user-generated spelling variants associated with each record to improve recognition, there has been no way to verify that the text matches the audio content of the recording once the recording has been separated from a compact disc and stored in a file in any format.